None of the error messages you listed are BDB error messages. squidGuard is not something that we do any testing on internally and you need reach out to them on the meaning of their error messages. What you could do is set up a DB_CONFIG file and add some parameters to that. Information on how to set up a DB_CONFIG file is located in our C API Reference manual. This will allow you to set up cache sizes and log file sizes. I do not know if squidGuard allows you to make calls into the BDB library - if so you can do a call to set_errfile and have any BDB error messages out to an output flie.